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author | Michael Brown <mcb30@ipxe.org> | 2015-04-14 17:53:13 +0100 |
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committer | Michael Brown <mcb30@ipxe.org> | 2015-04-14 17:53:13 +0100 |
commit | 7ca801d637de3e2941f02f376ee1f0e26eabdfcb (patch) | |
tree | d145554705718f0598a96ae837fa35561089396a /src/include/ipxe/efi/Protocol | |
parent | c6c7e78c42fff7b057ce32467ac6aa84bef94026 (diff) | |
download | ipxe-7ca801d637de3e2941f02f376ee1f0e26eabdfcb.zip ipxe-7ca801d637de3e2941f02f376ee1f0e26eabdfcb.tar.gz ipxe-7ca801d637de3e2941f02f376ee1f0e26eabdfcb.tar.bz2 |
[efi] Use the EFI_RNG_PROTOCOL as an entropy source if available
Entropy gathering via timer ticks is slow under UEFI (of the order of
20-30 seconds on some machines). Use the EFI_RNG_PROTOCOL if
available, to speed up the process of entropy gathering.
Note that some implementations (including EDK2) will fail if we
request fewer than 32 random bytes at a time, and that the RNG
protocol provides no guarantees about the amount of entropy provided
by a call to GetRNG(). We take the (hopefully pessimistic) view that
a 32-byte block returned by GetRNG() will contain at least the 1.3
bits of entropy claimed by min_entropy_per_sample().
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Diffstat (limited to 'src/include/ipxe/efi/Protocol')
-rw-r--r-- | src/include/ipxe/efi/Protocol/Rng.h | 158 |
1 files changed, 158 insertions, 0 deletions
diff --git a/src/include/ipxe/efi/Protocol/Rng.h b/src/include/ipxe/efi/Protocol/Rng.h new file mode 100644 index 0000000..f04efbb --- /dev/null +++ b/src/include/ipxe/efi/Protocol/Rng.h @@ -0,0 +1,158 @@ +/** @file + EFI_RNG_PROTOCOL as defined in UEFI 2.4. + The UEFI Random Number Generator Protocol is used to provide random bits for use + in applications, or entropy for seeding other random number generators. + +Copyright (c) 2013, Intel Corporation. All rights reserved.<BR> +This program and the accompanying materials are licensed and made available under +the terms and conditions of the BSD License that accompanies this distribution. +The full text of the license may be found at +http://opensource.org/licenses/bsd-license.php. + +THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, +WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. + +**/ + +#ifndef __EFI_RNG_PROTOCOL_H__ +#define __EFI_RNG_PROTOCOL_H__ + +FILE_LICENCE ( BSD3 ); + +/// +/// Global ID for the Random Number Generator Protocol +/// +#define EFI_RNG_PROTOCOL_GUID \ + { \ + 0x3152bca5, 0xeade, 0x433d, {0x86, 0x2e, 0xc0, 0x1c, 0xdc, 0x29, 0x1f, 0x44 } \ + } + +typedef struct _EFI_RNG_PROTOCOL EFI_RNG_PROTOCOL; + +/// +/// A selection of EFI_RNG_PROTOCOL algorithms. +/// The algorithms listed are optional, not meant to be exhaustive and be argmented by +/// vendors or other industry standards. +/// + +typedef EFI_GUID EFI_RNG_ALGORITHM; + +/// +/// The algorithms corresponds to SP800-90 as defined in +/// NIST SP 800-90, "Recommendation for Random Number Generation Using Deterministic Random +/// Bit Generators", March 2007. +/// +#define EFI_RNG_ALGORITHM_SP800_90_HASH_256_GUID \ + { \ + 0xa7af67cb, 0x603b, 0x4d42, {0xba, 0x21, 0x70, 0xbf, 0xb6, 0x29, 0x3f, 0x96 } \ + } +#define EFI_RNG_ALGORITHM_SP800_90_HMAC_256_GUID \ + { \ + 0xc5149b43, 0xae85, 0x4f53, {0x99, 0x82, 0xb9, 0x43, 0x35, 0xd3, 0xa9, 0xe7 } \ + } +#define EFI_RNG_ALGORITHM_SP800_90_CTR_256_GUID \ + { \ + 0x44f0de6e, 0x4d8c, 0x4045, {0xa8, 0xc7, 0x4d, 0xd1, 0x68, 0x85, 0x6b, 0x9e } \ + } +/// +/// The algorithms correspond to X9.31 as defined in +/// NIST, "Recommended Random Number Generator Based on ANSI X9.31 Appendix A.2.4 Using +/// the 3-Key Triple DES and AES Algorithm", January 2005. +/// +#define EFI_RNG_ALGORITHM_X9_31_3DES_GUID \ + { \ + 0x63c4785a, 0xca34, 0x4012, {0xa3, 0xc8, 0x0b, 0x6a, 0x32, 0x4f, 0x55, 0x46 } \ + } +#define EFI_RNG_ALGORITHM_X9_31_AES_GUID \ + { \ + 0xacd03321, 0x777e, 0x4d3d, {0xb1, 0xc8, 0x20, 0xcf, 0xd8, 0x88, 0x20, 0xc9 } \ + } +/// +/// The "raw" algorithm, when supported, is intended to provide entropy directly from +/// the source, without it going through some deterministic random bit generator. +/// +#define EFI_RNG_ALGORITHM_RAW \ + { \ + 0xe43176d7, 0xb6e8, 0x4827, {0xb7, 0x84, 0x7f, 0xfd, 0xc4, 0xb6, 0x85, 0x61 } \ + } + +/** + Returns information about the random number generation implementation. + + @param[in] This A pointer to the EFI_RNG_PROTOCOL instance. + @param[in,out] RNGAlgorithmListSize On input, the size in bytes of RNGAlgorithmList. + On output with a return code of EFI_SUCCESS, the size + in bytes of the data returned in RNGAlgorithmList. On output + with a return code of EFI_BUFFER_TOO_SMALL, + the size of RNGAlgorithmList required to obtain the list. + @param[out] RNGAlgorithmList A caller-allocated memory buffer filled by the driver + with one EFI_RNG_ALGORITHM element for each supported + RNG algorithm. The list must not change across multiple + calls to the same driver. The first algorithm in the list + is the default algorithm for the driver. + + @retval EFI_SUCCESS The RNG algorithm list was returned successfully. + @retval EFI_UNSUPPORTED The services is not supported by this driver. + @retval EFI_DEVICE_ERROR The list of algorithms could not be retrieved due to a + hardware or firmware error. + @retval EFI_INVALID_PARAMETER One or more of the parameters are incorrect. + @retval EFI_BUFFER_TOO_SMALL The buffer RNGAlgorithmList is too small to hold the result. + +**/ +typedef +EFI_STATUS +(EFIAPI *EFI_RNG_GET_INFO) ( + IN EFI_RNG_PROTOCOL *This, + IN OUT UINTN *RNGAlgorithmListSize, + OUT EFI_RNG_ALGORITHM *RNGAlgorithmList + ); + +/** + Produces and returns an RNG value using either the default or specified RNG algorithm. + + @param[in] This A pointer to the EFI_RNG_PROTOCOL instance. + @param[in] RNGAlgorithm A pointer to the EFI_RNG_ALGORITHM that identifies the RNG + algorithm to use. May be NULL in which case the function will + use its default RNG algorithm. + @param[in] RNGValueLength The length in bytes of the memory buffer pointed to by + RNGValue. The driver shall return exactly this numbers of bytes. + @param[out] RNGValue A caller-allocated memory buffer filled by the driver with the + resulting RNG value. + + @retval EFI_SUCCESS The RNG value was returned successfully. + @retval EFI_UNSUPPORTED The algorithm specified by RNGAlgorithm is not supported by + this driver. + @retval EFI_DEVICE_ERROR An RNG value could not be retrieved due to a hardware or + firmware error. + @retval EFI_NOT_READY There is not enough random data available to satisfy the length + requested by RNGValueLength. + @retval EFI_INVALID_PARAMETER RNGValue is NULL or RNGValueLength is zero. + +**/ +typedef +EFI_STATUS +(EFIAPI *EFI_RNG_GET_RNG) ( + IN EFI_RNG_PROTOCOL *This, + IN EFI_RNG_ALGORITHM *RNGAlgorithm, OPTIONAL + IN UINTN RNGValueLength, + OUT UINT8 *RNGValue + ); + +/// +/// The Random Number Generator (RNG) protocol provides random bits for use in +/// applications, or entropy for seeding other random number generators. +/// +struct _EFI_RNG_PROTOCOL { + EFI_RNG_GET_INFO GetInfo; + EFI_RNG_GET_RNG GetRNG; +}; + +extern EFI_GUID gEfiRngProtocolGuid; +extern EFI_GUID gEfiRngAlgorithmSp80090Hash256Guid; +extern EFI_GUID gEfiRngAlgorithmSp80090Hmac256Guid; +extern EFI_GUID gEfiRngAlgorithmSp80090Ctr256Guid; +extern EFI_GUID gEfiRngAlgorithmX9313DesGuid; +extern EFI_GUID gEfiRngAlgorithmX931AesGuid; +extern EFI_GUID gEfiRngAlgorithmRaw; + +#endif |